A stepper motor is always brushless Think of it as a 3 phase stepper instead of 2 or 4 phase steppers.

@tylerntIf you'd like to tinker a bit with the idea, just slaughter some PC cooling fans ( eg. from old PSU )They usually have a high winding resistance. A 12V fan would probably work directly with the 5V arduino pins, but don't take my word for it!

I don't think you'd need an encoder or anything. Just let the IMU do all the work.

It's not my fault when my Posts are full of Errors. This stupid autocorrection from my browser is set up for german grammar.

Just found out which driver circuit the open-source BLDC gimbal "AlexMOS" guys are using:http://www.alldatasheet.com/datasheet-pdf/pdf/22545/STMICROELECTRONICS/L6234.htmlIncludes freewheeling diodes and current sensing.Available in 20 pin DIP *hint*

It's not my fault when my Posts are full of Errors. This stupid autocorrection from my browser is set up for german grammar.

Just found out which driver circuit the open-source BLDC gimbal "AlexMOS" guys are using:http://www.alldatasheet.com/datasheet-pdf/pdf/22545/STMICROELECTRONICS/L6234.htmlIncludes freewheeling diodes and current sensing.Available in 20 pin DIP *hint*

So you knew how to solve the problem with BLDC? Can you take a tutorial for me?

Just found out which driver circuit the open-source BLDC gimbal "AlexMOS" guys are using:http://www.alldatasheet.com/datasheet-pdf/pdf/22545/STMICROELECTRONICS/L6234.htmlIncludes freewheeling diodes and current sensing.Available in 20 pin DIP *hint*

So you knew how to solve the problem with BLDC? Can you take a tutorial for me?

Sorry my friend,I have no hands on experience with that stuff. I just gave my 2 Cents. Try out a small fan Motor from a CPU cooler, their winding resistance might be high enough to drive them directly with a arduino. Start with two phases at first. See what happens when you change PWM ratio for one phase. Use a potmeter on an analog Input to change pwm ratio on the fly.

A full test setup would have three potmeters for three phases. Find out a pattern to rotate the fan slowly.

Good luckO_LampePS: It might be necessary to switch polarity for the phases too. Then ofcourse you'have to recalculate your pwm, since the duty cycle would change too.

It's not my fault when my Posts are full of Errors. This stupid autocorrection from my browser is set up for german grammar.

Electronic Technician, Electronic Engineering Technician
I love to build things. Test equipment, replica and original sci fi props and costume pieces, and whatever else I feel like at the time. I have an Ultimaker and a 3D engraver. I rarely put a kit tog

Brushless DC motors have stationary electromagnets, so it might be possible to rewind some with more turns of finer wire. No worries about balance, then, other than getting the same number of windings.

If you have some kind of optical encoder on the shaft, you'd have rotational feedback for the Arduino to calculate what voltage/current/PWM each phase requires.

Electronic Technician, Electronic Engineering Technician
I love to build things. Test equipment, replica and original sci fi props and costume pieces, and whatever else I feel like at the time. I have an Ultimaker and a 3D engraver. I rarely put a kit tog

PoppyAnn

Has no one on here ever heard of a brushless gimbal motor? the reason for using a brushless motor on a gimbal is that they are much faster and smoother than any servo, they are available from most good radio control model shops, here are a couple of cheep ones from hobby king :-https://www.hobbyking.com/hobbyking/store/__62564__2206_140Kv_Brushless_Gimbal_Motor_Ideal_for_GoPro_style_Cameras_UK_Warehouse_.html

there is no encoder except for a 3 axial accelerometer and the brushless motor controller, the motors are used on a one to one ratio no gearing is used, these type of brushless motors are of a different type of motor as they have been wound with many coils of fine wire not as normal ones which have few coils of heavy wire.

I hope this may help people who have not come across these type of motors before.